System and method for patient positioning in an automated surgery

ABSTRACT

The present solution is generally directed to a patient positioning system used to position body parts, such as a knee, during a medical or surgical procedure. Further, the present solution is generally directed to a system and method for establishing and tracking virtual boundaries, and controlling a patient positioning system to adjust those virtual boundaries to facilitate an automated surgery procedure. Further, the present solution is generally directed to the synergistic combination of an autonomous patient positioning sub-system with a robotic surgical manipulator sub-system.

BACKGROUND OF THE SOLUTION Technical Field

The present solution is generally directed to a patient positioningsystem used to position body parts, such as a knee, during a medical orsurgical procedure. The present solution also is generally directed to asystem and method for controlling a surgical manipulator and a patientpositioning system based on automated surgical parameters. Further, thepresent solution is generally directed to a system and method forestablishing and tracking virtual boundaries, and controlling a patientpositioning system to adjust those virtual boundaries to facilitate anautomated surgery procedure.

Further, the present solution is generally directed to the synergisticcombination of an autonomous patient positioning sub-system with arobotic surgical manipulator sub-system. The combination of theautonomous patient positioning sub-system with the robotic surgicalmanipulator sub-system is ready, relatively simple to accomplish, andrelatively easy to program in conjunction with the pre-existing softwareand hardware for the autonomous or partially-autonomous combinationsystem.

Prior Art

Orthopedic surgeons have found it useful to use robotic devices toassist in performing surgical procedures. Generally, these roboticdevices comprise a moveable arm with one or more linkages, and a freedistal end, with an attached surgical instrument, that can be accuratelyand precisely applied to the surgical site. The practitioner, with theaid of computer software, machine learning, and/or specialty algorithmsfor sensory input, is able to position the arm so as to position thesurgical instrument at the site on the patient at which the instrumentis to perform the surgery.

Advantageously, the robotic device, unlike the surgeon, is not subjectedto muscle strain, fatigue, or involuntary movements. Thus, in comparisonto when an instrument is handheld and, therefore, hand positioned andsupported, it is possible to use the robotic device to hold aninstrument steady and consistently, and move the instrument along adefined path with a high degree of accuracy and precision.

Further, some robotic devices are designed to be used with surgicalnavigation systems. Generally, a navigation system is configured toprocess sensor data and provide an indication of the location of thesurgical instrument relative to the location of the patient againstwhich the instrument is applied. In some instances, virtual boundariesare created using computer aided design software to delineate areas inwhich an end surgical tool of a robotic device/system can maneuver fromareas in which the end surgical tool cannot. This substantiallyeliminates the likelihood that the instrument will act, or be requestedto act, outside its intended bounds/margins (i.e., too much being done,or treatment being performed on the incorrect location). Conversely,this substantially eliminates the likelihood that the instrument willnot act, or be requested to not act, on the intended bounds/margins(i.e., too little being done).

More specifically, when a robotic device is provided with dataindicating the relative location of the instrument, the robotic devicemay be configured to autonomously or semi-autonomously position theinstrument to ensure that it is applied to the intended site on thepatient. In orthopedic surgery, a virtual cutting boundary is created todelineate sections of bone to be removed by the end surgical tool duringthe surgery from sections of bone that are to remain after the surgery.The navigation system tracks movement of the end surgical tool withrespect to the virtual cutting boundary to determine a position and/ororientation of the end surgical tool relative to the virtual cuttingboundary. The robotic system cooperates with the navigation system toguide movement of the end surgical tool so that the end surgical tooldoes not move beyond the virtual cutting boundary.

Typically, virtual cutting boundaries are created prior to surgery.Virtual cutting boundaries are created in a model of a patient's bone,and fixed with respect to the bone, so that when the model is loadedinto the navigation system, the navigation system tracks movement of thevirtual cutting boundary by tracking movement of the bone. Virtualboundaries also define other anatomical features to be avoided by theend surgical tool during surgery. Such features include nerves or othertypes of tissue to be protected from contact with the end surgical tool.Virtual boundaries also are used to provide virtual pathways that directthe end surgical tool toward the anatomy being treated. These examplesof virtual boundaries may be fixed in relationship to the anatomy beingtreated, or the boundaries may be dynamic and tracking of the anatomicalfeatures, and other objects in the operating room or surgical space,which may move relative to the anatomy being treated.

During performance of an orthopedic surgical procedure, a number ofdifferent surgical components are typically positioned at the surgicalsite. Further, there is a need to properly position a patient, includinga limb, for the procedure. Some procedures require that the patient orpatient's limb be re-positioned during different parts of the procedure.One method of positioning patients during surgical procedures has beenthe use of an assistant surgeon or other trained personnel to on-site,manually operate, maneuver, and judge the position adjustments of thepatient. The trained personnel performs, at least in part, via specialtypatient positioning tools/devices. However, this method has severaldisadvantages including the costs involved with using additionaloperating-room personnel (to operate the patient positioningtools/devices), and the risk involved with positioning that personnelproximate to the sterile operating field (which risks infection).

Therefore, there is a need in the art to provide a system and method forcontrolling automated patient positioning devices in conjunction withestablished or establishing virtual constraint boundaries.

Providing some further context, certain exemplary embodiments of thepresent solution are directly applicable to arthroplasty. In the case ofboth knee and hip arthroplasty, this procedure can help relieve pain andrestore function in a severely diseased joint. This treatment optioninvolves cutting away damaged bone and cartilage (with an end surgicaltool, for example) and replacing it with an artificial joint made ofmetal alloys, high-grade plastics and/or polymers. This type oftreatment procedure known in the art produces reliable symptomaticrelief and improved function.

Prior to placing the patient on a surgical table, it is common practiceto place a sterile drape on the table. This drape functions as a sterilebarrier. Some available limb holders for arthroplasty are designed to beattached directly to the tables with which the holders are used. At thelocation where this type of limb holder is attached it is difficult, ifnot impossible to, place the drape around and/or under the limb holderso as to provide the desired sterile barrier.

More specifically, hip and knee joint replacements are the most commonlyperformed joint replacement surgical procedures in which parts of anarthritic or damaged joint is removed and replaced with a metal, plasticor ceramic device termed joint implants. Joint implants or what commonlycan be referred to as prosthetic joints, are long-term implantablesurgical devices that are used to either completely or partially replacethe structural elements within the musculoskeletal system to improve andenhance the function of a joint.

Physiology changes to the above mentioned joint structures are thoughtto contribute towards the progression of a diseased knee joint leadingto the consideration of joint replacement surgery. Some of these changesinclude: measureable differences in overall knee cartilage volume andtibial cartilage volume, measurable differences in bone size, meniscaltears and bone marrow lesions.

Pursuant to the foregoing, it may be regarded as an object of thepresent solution to overcome the deficiencies of, and provide forimprovements in, the state of the prior art as described above, and asmay be inherent in the same, or as may be known to those skilled in theart. It is a further object of the present solution to provide asurgical device and method of use thereof, for carrying out the same,and of the foregoing character, and in accordance with the aboveobjects, which may be readily carried out, with and within the process,and with comparatively simple equipment, and with relatively simpleengineering requirements. Still further objects may be recognized andbecome apparent upon consideration of the following specification, takenas a whole, wherein by way of illustration and example, an embodiment ofthe present solution is disclosed.

As used herein, any reference to an object of the present solutionshould be understood to refer to aspects and advantages of the presentsolution, which flow from its conception and reduction to practice, andnot to any a priori or prior art conception.

The above and other objects of the present solution are realized andsome limitations of the prior art are overcome in the present solutionby providing new and improved methods, processes, compositions, andsystems. A better understanding of the principles and details of thepresent solution will be evident from the following description.

BRIEF SUMMARY OF THE SOLUTION

An exemplary embodiment of the present solution relates to a system andmethod for positioning a patient in an automated surgical environment.

An exemplary embodiment of the present solution also relates to anautonomous patient positioning system and method of operation (1) thatis simple in construction, (2) that is easy to integrate with anorthopedic robotic surgery device/system, (3) that is positioned outsidethe sterile operating field, and (4) that allows for manual positioningof the patient, in and out of the patient positioning system, whennecessary, without the patient having to be physically strapped (at theupper leg or foot, for example), and (5) yet permits a systemprocessor(s), as monitored and supervised by a surgeon, to readilyposition, adjust, and/or re-position a patient's limbs during theautomated surgical procedure.

In accordance with one aspect of the present solution, an autonomouspatient positioning device is provided and includes a support adapted tobe positioned against a predetermined portion of a patient's body; adrive mechanism for moving the support along a generally linear path; asource of power for the drive mechanism; a bracket for mounting thedrive mechanism to an operating table; and a remote device for actuatingthe drive mechanism. The remote device uses, at least in part, aplurality of dynamic virtual boundaries to guide movement of the patientpositioning device/sub-system.

In a preferred form, the support is padded to provide additional comfortfor a patient. In one embodiment, the support is generally cylindricalin shape. The support may be adapted to be positioned against anypredetermined portion of a patient's body. In one embodiment of thesolution, the support is designed to be positioned against the foot of apatient.

Further, the drive mechanism may comprise a number of electrically,hydraulically, or pneumatically operated devices. In one embodiment ofthe solution, the drive mechanism comprises an electrically poweredlinear actuator. In a preferred form, the support includes an extension,preferably angled, and the drive mechanism is coupled to the extension.Preferably, the extension includes means for adjusting the height of thesupport. In one embodiment of the solution, the means include aplurality of generally spaced openings on the extension and a pin forreleasably locking the extension in a predetermined position throughsuch spaced openings.

The device of the present solution provides convenience for the surgeonby permitting remote and autonomous “smart” operation of the drivemechanism. The present solution also provides a method for positioning apatient during a surgical procedure comprising positioning a patient onan operating table; positioning a movable support against apredetermined portion of a patient's body outside of the sterileoperating field; causing the support to move by actuating a drivemechanism to provide linear movement of the support to cause the patientto move to an optimal position for a surgical procedure.

In certain exemplary embodiments, the autonomous patient positioningsub-system is communicatively coupled with a navigation system, andindirectly to a surgical manipulator for applying an instrument orsurgical tool to a patient. The navigation system is configured tocooperate with the autonomous patient positioning sub-system to positionthe support. The navigation system includes a navigation processor and aboundary generator module operable on the navigation processor or anyother processor. The boundary generator module is configured to generatethe boundary based on a plurality of inputs including data defining animplant to be fitted to the patient, for example, and data defining howrelative changes to the patient positioning sub-system affect theposition and pose of the tissue of the patient receiving the implant.

In certain exemplary embodiments, the system comprises a support portiontracking device to track movement of the support. The system may alsocomprise a first boundary tracking device to track movement of a firstof the plurality of virtual boundaries wherein the first virtualboundary is associated with the anatomy to be treated. The system mayfurther comprise a second boundary tracking device to track movements ofa second of the plurality of virtual boundaries wherein the secondvirtual boundary is associated with an object to be avoided by thesurgical tool or instrument. A controller is configured to receiveinformation associated with the tracking devices including positions ofthe system portion relative to the first and second virtual boundaries.The controller is configured to guide movement of the support portion ofthe patient positioning sub-system relative to each of the first andsecond virtual boundaries as the first and second virtual boundariesmove relative to one another.

In a preferred embodiment, the movable support is positioned against thepatient's heel and foot. Movement of the support causes flexing of thepatient's knee to a target position for a surgical procedure. Dependingon the surgical procedure to be performed, the support may be moved to asecond position during the surgical procedure, etc. Additional movementof the support during surgery is possible and simplified, depending uponthe need for re-positioning of the patient.

A method of controlling the support of the patient positioningsub-system is also provided. The method includes providing the patientpositioning sub-system to properly position a patient at certain pointsduring a surgical procedure. The navigation system cooperates with thepatient positioning sub-system to position the support with respect to aboundary between tissue of the patient to which the surgical tool shouldbe applied and tissue of the patient to which the tool should not beapplied. The boundary is generated based on a plurality of inputs.

In another embodiment, a method is provided for using a plurality ofdynamic virtual boundaries to guide movement of the support of thepatient positioning sub-system. The method includes tracking movement ofthe support and a first virtual boundary associated with the anatomy tobe treated. The method further includes tracking movement of a secondvirtual boundary relative to the first virtual boundary wherein thesecond virtual boundary is associated with an object to be avoided bythe surgical instrument. Movement of the support is guided relative toeach of the first and second virtual boundaries as the first and secondvirtual boundaries move relative to one another.

One advantage of these embodiments is the ability to dynamically trackobjects (such as other tools or anatomy) that may move relative to theanatomy of interest, in addition to tracking the patient positioningsub-system. The second virtual boundary can be a virtual constraintboundary or other type of virtual boundary that is tracked for movementrelative to the first virtual boundary associated with the anatomy.

Embodiments of the system and sub-systems described herein, according tothe solution, are not limited to the exemplary aspects and featuresdescribed above or below. Certain embodiments may include additionalfeatures, or different features, while other embodiments includealternative features.

BRIEF DESCRIPTION OF THE DRAWINGS

In the Figures, like reference numerals refer to like parts throughoutthe various views unless otherwise indicated. For reference numeralswith letter character designations such as “102A” or “102B”, the lettercharacter designations may differentiate two like parts or elementspresent in the same Figure. Letter character designations for referencenumerals may be omitted when it is intended that a reference numeral toencompass all parts having the same reference numeral in all Figures.

FIG. 1 is an illustration of an exemplary embodiment of a new and usefulsystem that positions a patient, via an autonomous patient positioningsub-system, and which operates in conjunction with a robotic surgicalmanipulator device;

FIG. 2 is a block diagram of a number of modules that collectivelycooperate to control actuation of the overall system of FIG. 1;

FIG. 3 is a magnified, side view of the exemplary system of FIG. 1;

FIGS. 4A-4C are a flow chart of an exemplary embodiment of a method ofusing the system of FIGS. 1-3; and

FIG. 5 is an illustration of a second exemplary embodiment of a new anduseful system that positions a patient, via an autonomous patientpositioning sub-system, and which operates in conjunction with a roboticsurgical manipulator device, including an autonomous side pad.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

For a further understanding of the nature, function, and objects of thepresent solution, reference should now be made to the following detaileddescription. While detailed descriptions of the preferred embodimentsare provided herein, as well as the best mode of carrying out andemploying the present solution, it is to be understood that the presentsolution may be embodied in various forms. Therefore, specific detailsdisclosed herein are not to be interpreted as limiting, but rather as abasis for the claims and as a representative basis for teaching oneskilled in the art to employ the present solution in virtually anyappropriately detailed system, structure, or manner.

The word “exemplary” is used herein to mean serving as an example,instance, or illustration. Any aspect described herein as “exemplary” isnot necessarily to be construed as exclusive, preferred or advantageousover other aspects.

In this description, the term “application” may also include fileshaving executable content, such as: object code, scripts, byte code,markup language files, and patches. In addition, an “application”referred to herein, may also include files that are not executable innature, such as documents that may need to be opened or other data filesthat need to be accessed.

As used in this description, the terms “component,” “database,”“module,” “system,” and the like are intended to refer to acomputer-related entity, either hardware, firmware, a combination ofhardware and software, software, or software in execution. For example,a component may be, but is not limited to being, a process running on aprocessor, a processor, an object, an executable, a thread of execution,a program, and/or a computer. By way of illustration, both anapplication running on a computing device and the computing device maybe a component.

One or more components may reside within a process and/or thread ofexecution, and a component may be localized on one computer and/ordistributed between two or more computers. In addition, these componentsmay execute from various computer readable media having various datastructures stored thereon. The components may communicate by way oflocal and/or remote processes such as in accordance with a signal havingone or more data packets (e.g., data from one component interacting withanother component in a local system, distributed system, and/or across anetwork such as the Internet with other systems by way of the signal).

In this description, the terms “central processing unit (“CPU”),”“digital signal processor (“DSP”),” “graphical processing unit (“GPU”),”“processing component” and “chip” are used interchangeably. Moreover, aCPU, DSP, GPU or chip may be comprised of one or more distinctprocessing components generally referred to as “core(s).”

The present solution is based, at least in part, on a new and usefulpatient positioning system that autonomously positions a patient for anumber of surgical procedures including, but not limited to, total hipreplacement, lumbar surgery, open reduction internal fixation of theelbow, open reduction internal fixation of the femur, foot fusion,posterior cruciate ligament reconstruction, shoulder repairs, totalshoulder replacement, spinal fusion, open reduction internal fixation ofthe tibia, anterior cervical discectomy and fusion of the neck,arthroscopic anterior cruciate ligament reconstruction, arthroscopicknee evaluation, and partial and total knee replacement. It will also beunderstood that the construction of the support portion of thesystem/sub-system may be modified to accommodate specific body partsdepending upon the surgical procedure being performed. While certainexemplary embodiments in the following detailed description are madewith respect to positioning a patient's knee for a surgical procedure,it will be understood that the solution encompasses other surgicalprocedures and that the following description is made with reference toa preferred embodiment thereof and to simplify understanding of thesolution.

At a very high level, an exemplary embodiment of the present solutionrelates to an apparatus for positioning a patient on an operatingtable—or a patient positioning sub-system.

An exemplary embodiment of the patient positioning sub-system of thepresent solution includes a support that is adapted to be positionedagainst a predetermined portion of a patient's body, such as beneath thepatient's foot, for example. The patient positioning sub-system alsoincludes a drive mechanism for moving the support along a generallylinear path. The drive mechanism may be electrically, hydraulically, orpneumatically powered. In a preferred embodiment, the drive mechanismcomprises an electrically powered linear actuator.

Further, a bracket is used to secure the drive mechanism to a supportrail of a surgical operating table or bed. Thumbscrews, clamps, or otherattachment devices are used. The bracket and attachments are designed sothat the drive mechanism is readily moveable from one side of anoperating table to an opposite side or end, depending upon theparticular surgical procedure to be performed.

Further, the support may be padded for patient comfort. In a preferredembodiment, the support is in the form of a cylinder; however, it isenvisioned that the support may take different forms as required by thesurgical procedure selected.

In use, in an exemplary embodiment, a patient is positioned on theoperating table and the patient positioning sub-system is installed sothat the movable support is properly positioned against a predeterminedportion of the patient's body (the support is positioned beneath thefoot of the patient, for example). The patient positioning sub-systemand/or the movable support may then be positioned and used outside ofthe sterile operating field (below the sterile drape, for example),advantageously not interfering with a patient's, surgeon's, and/or othersurgical assistant's movement.

As is presented in detail herein, in some surgical procedures, it isnecessary to move a patient's limb or body to a first position forinitial work and then to move that limb or body portion to second, thirdor more optimal positions as the surgery proceeds. The patientpositioning system of the present solution facilitates this end betterthan any system known or used in the art.

The present solution also is based, at least in part, on a new anduseful system that positions a patient, via an autonomous patientpositioning sub-system, in conjunction with a robotic surgicalmanipulator device that positions a surgical instrument or tool for useon the patient, wherein the positioning of the patient is based at leastin part on the demands and requirements and boundary-requirements, etc.of the robotic surgical manipulator device.

Robotic surgical manipulator device(s) usually comprise a moveable armwith one or more linkages, and a free distal end, with an attachedsurgical instrument or tool, that can be accurately and preciselyapplied to the patient, and the necessary computing, processing, andtransmission hardware to make the system work. When robotic device(s)are provided with data indicating the relative location of theinstrument, the robotic device(s) are configured to autonomously orsemi-autonomously position the instrument to ensure that it is appliedto the intended site on the patient.

Virtual cutting boundaries are created to delineate sections availableto the instrument and section restricted to the instrument. Navigationsystem(s), for example, track movement of the end surgical tool withrespect to the virtual cutting boundary to determine a position and/ororientation of the end surgical tool relative to the virtual cuttingboundary. Navigation system(s) also interface with other known computerhardware component(s) to actuate the end surgical tool. The presentdisclosure explores the benefits of incorporating an automated patientpositioning system.

As such, an exemplary embodiment of the patient positioning sub-systemof the present solution, configured to operate in conjunction with arobotic surgical manipulator device, comprises a surgical processingcomponent/sub-system configured to process data from the system, toprovide an indication of the location of the surgical instrumentrelative to the location of the patient, and to assess the state,position, and/or condition of the components or sub-components and howthat information relates to the virtual boundaries. For example, thesurgical processing component/sub-system may be configured to receiveand process sensor data and/or component data to create virtualboundaries for the surgery, and to process the position of the movableportions of the patient positioning sub-system, and to assess howrelative changes to the position of the movable portions affectaccessibility to the patient tissue and/or locations defined by thevirtual boundaries.

The exemplary embodiment of the patient positioning sub-system alsocomprises a controller sub-system, to which the surgical navigationsub-system communicates information, for which the controller sub-systemuses to appropriately actuate the patient positioning sub-system(actuating back and forth movement of the support of the patientpositioning sub-system, relative to the surgical table's longitudinalaxis, for example—towards the feet of the table or towards the head ofthe table).

As is presented in detail herein, during performance of an orthopedicsurgical procedure, a number of different surgical components aretypically positioned at the surgical site. For example, joint componentssuch as trial implants are positioned at the surgical site to determinethe appropriately sized implant components that should be permanentlyfitted to the patient. Other examples include retractors and trackers,etc. as well as any other surgical instrument known to a person havingordinary skill in the art

Further, some anatomical features, or other objects in the operatingroom, may move relative to the anatomy being treated. For instance,retractors used to provide an opening in tissue for a surgical tool, aninstrument, etc. may move relative to the anatomy being treated. If notaccurately tracked using an appropriate dynamic virtual constraintboundary system, for example, the robotic surgical manipulator devicesmay inadvertently strike objects or boundaries that are not desiredand/or provide incorrect information to the person overseeing thesurgery. If overly restricted, a surgeon using the robotic surgicalmanipulator devices is not afforded the full capability necessary tofinish complex and dynamic surgeries.

Further, and as context, in current practice, each joint component of anorthopedic joint system is typically packaged separately. Due tomanufacturing variation, each of these joint components has dimensionswhich vary slightly from others of their type. A typical kneereplacement will use three or more joint components. The collectivevariation of these dimensions is known as dimensional stack-up.

In conventional knee replacement surgery, the dimensional stack-up isrelatively small compared to other potential sources of alignment andplacement error such as jig placement or cut errors. Options areavailable for users to change joint components in order to make up forthese collective errors and achieve a proper and optimal fit.

There is therefore a need to improve prior art patient positioningsub-systems and prior art robotic surgical manipulator devices toresolve these issues, and various other issues. The exemplaryembodiments of the patient positioning sub-system, in conjunction with arobotic surgical manipulator device, of the present solution,facilitates this end better than any system known or used in the art.

The present solution also is based, at least in part, on a new anduseful system that positions a patient, via a patient positioningsub-system, operated in conjunction with a robotic surgical manipulatordevice, wherein the positioning of the patient is an autonomous mode,coordinated with the application of the surgical instrument or tool ofthe surgical manipulator. More specifically, the surgical instrument ofthe robotic surgical manipulator device determines the relative locationof the instrument to a boundary, and determines the relativelocation/positioning of the patient positioning sub-system (the supportof the patient positioning sub-system, for example), with the patient inplace. This boundary defines the limits of the tissue beyond which theinstrument should not be placed. In the event it appears that therobotic surgical manipulator device demands, requires, or needspositioning of the instrument beyond the boundary, the manipulator doesnot allow this movement of the instrument.

For example, should the robotic surgical manipulator device determinethat the needed path/point for the instrument would result in theinstrument exceeding a boundary, which the instrument should not cross,the surgical manipulator (1) prevents the instrument from movementbeyond the boundary, and (2) adjusts the patient positioning sub-system(the support of the patient positioning sub-system, for example, and/orany other component or sub-system of the patient positioning sub-system)to reposition the tissue to be treated, and (3) reassesses/determinesthe relative location of the instrument to the new boundary condition,after adjustment of the patient positioning sub-system at (2). Therobotic surgical manipulator device may then continue to attempt to movethe instrument as demanded, required, or needed prior to (1).

In this way, at a very high level, an exemplary embodiment of thepresent solution relates to a robotic surgical device that realizes thesynergistic combination of an autonomous patient positioning sub-systemwith a robotic surgical manipulator sub-system, the combination forpositioning a surgical instrument for use on the patient, and forcontrolling the surgical instrument based on tissue parameters and/orimplant parameters and/or the parameters of the patient positioningsub-system (the support of the patient positioning sub-system, forexample).

Described in an alternative way, an exemplary embodiment of the presentsolution relates to a robotic surgical device that realizes thesynergistic combination of an autonomous patient positioning sub-systemwith a robotic surgical manipulator sub-system. The combination of theautonomous patient positioning sub-system with the robotic surgicalmanipulator sub-system is ready, relatively simple to accomplish, andrelatively easy to program in conjunction with the programming for theautonomous or partially-autonomous robotic surgical manipulatorsub-system as described herein. Advantageously, the combination of theautonomous patient positioning sub-system with the robotic surgicalmanipulator sub-system results in a final system and method that (1)yields advantages and benefits that are more than what would beexpected, and (2) yields advantages and benefits that would not begained by simply making any other seemingly equivalent combination.Advantages and benefits realized by the final system and method includefaster surgery times, decreased risk of infection during surgery, moreefficient and effective use of surgery resources and personnel, moreaccurate and precise application of surgical tools, and decreased needfor a specialized, cumbersome set-up for use on the combined finalsystem to make it operable.

In fact, there are countless examples of prior art patient positioningsub-systems that, if combined with prior art robotic surgicalmanipulator sub-system(s), would not yield the synergistic advantagesand benefits as described in the present disclosure.

As such, prior art patient positioning devices would be representativeof components that, if combined with a prior art robotic surgicalmanipulator sub-system, would not yield the synergistic advantages andbenefits as described in the present disclosure. Combinations with mostif not all of the prior art would at best be a sum of the components, ifnot less than the sum of the components. In stark contrast to this, thepresent solution realizes the synergistic combination of an autonomouspatient positioning sub-system, with a robotic surgical manipulatorsub-system, and suffers few to no complications.

For example, and related to complications, fixed/static prior artdevices are those that are positioned, secured, or mounted on anoperating table prior to the start of the surgical procedure. Once theprocedure begins, such devices cannot be easily moved, adjusted, orre-positioned. Thus, if a surgical procedure requires that the patientbe re-positioned during different parts of the procedure, the pior artcurrently teaches that surgery must be temporarily halted while thepatient positioning device is moved or hand- adjusted, typically throughthe use of thumbscrews, levers, sliding bars, and the like.

Further, mechanically, electrically, or hydraulically-driven deviceshave also been suggested, which teach an apparatus for holding,maneuvering, and maintaining a body part of a patient during surgery.One embodiment of the device physically straps the upper leg and foot ofa patient to supports that are movable using motor driven gears thatprovide lateral, tilting, and swinging movement. However, such a deviceis mechanically complex and requires sterilization of portions of thedevice that are located in the sterile operating field. Further, oncethe patient is strapped into the device, manual positioning of the legis not possible. The present solution solves these problems.

Accordingly, the need exists in the art for an automated patientpositioning device and method that is simple in construction, easy toinstall and position, and that can be used outside the sterile operatingfield, in conjunction with a robotic surgical manipulator sub-system.

Anthropometrics

It is envisioned that weight may be measured to the nearest 0.1 kg (withthe subject's shoes, socks, and bulky clothing removed), with a singlepair of electronic scales that will calibrate the weight. Height may bemeasured to the nearest 0.1 cm (with shoes and socks removed) using astadiometer. Body mass index (BMI) may be calculated as weight(kg)/height (m²).

Computerized Tomography (CT Scan)

A computerized tomography (CT) scan combines a series of X-ray imagestaken from different angles and uses computer processing to createcross-sectional images of the bones to provide more detailed informationabout the structure of the bones. It is envisioned that a CT scan may beused to visualize the whole joint of both the healthy knee or hip jointand the diseased knee or hip joint to allow for a customized fit, forexample. Further, prior to the start of a procedure, pre-operativeimages of the location of the site on the patient at which theprocedures are performed are generated. These images may be based on MRIscans, radiological scans or computed tomography (CT) scans of thesurgical site. These images are mapped to the bone coordinate system,for example, using known methods.

Pre-Surgery Preparation

Before treating a patient, certain preparations are necessary such asdraping the patient and preparing the surgical site for treatment. Forinstance, in knee arthroplasty, surgical personnel may simply place andrest the leg/foot of interest upon the patient positioning sub-system,after having draped the patient and equipment. Other preparationsinclude placing objects needed for surgery in the operating room. Theseobjects can include leg holders, retractors, suction/irrigation tools,surgical personnel, and the like. During the surgery, these objects areto be avoided by the surgical instrument(s). To facilitate avoidance ofthese objects during the surgery, position information for one or moreof these objects is determined either directly or indirectly. In someembodiments, one or more of the objects are dynamically tracked by thenavigation sub-system during the surgery.

Hardware Patient Positioning Sub-System

It is envisioned, in one exemplary embodiment, that a patientpositioning sub-system is provided and includes a support adapted to bepositioned against a patient's heel; an electrically powered linearactuator as part of a drive mechanism, for moving the support along agenerally linear path; a source of power for the drive mechanism; abracket for mounting the drive mechanism to an operating table; and aremote device for actuating the drive mechanism.

More specifically, it is envisioned that the bracket is used to securethe drive mechanism to the support rail(s) of the surgery table, andthat the drive mechanism is anchored to the bracket(s). Thumbscrews,clamps, or other attachment devices may be used. The bracket andattachments are designed so that the drive mechanism is readily moveablefrom one side of an operating table to an opposite side or end,depending upon the particular surgical procedure to be performed, or thedemands of the virtual boundary. It also is envisioned that the actuatorincludes a motor, worm gearing, and a lead screw, and a thrust tube.Power to the motor causes rotation of the worm screw drive resulting inthe thrust tube either extending or retracting. The remote device foractuating the drive mechanism controls power to the motor and iscommunicatively coupled to other components/sub-systems, such as anavigation sub-system and/or other processing unit. The linear actuatormay be a commercially available device such as linear drives fromMagnetic Corporation of Olney, Ill., a subsidiary of SKF Linear Motion.Further, the source of power for the drive mechanism is provided throughan electrical plug.

It is envisioned, in one exemplary embodiment, that the support of thepatient positioning sub-system is padded and cylindrical in shape, toprovide additional comfort for a patient's heel/foot. The movablesupport is positioned under the patient's foot proximate or on the heel.Movement of the support causes flexing of the patient's knee to anoptimal position for a surgical procedure, and for adjusting of thevirtual boundaries as needed.

In this light, a method of controlling the support of the patientpositioning sub-system is also provided. A navigation system, whetherincorporated into the patient positioning sub-system and/or whetherestablished as its own as an independent component in the system,cooperates with the patient positioning sub-system to position thesupport with respect to a boundary between tissue of the patient, towhich the surgical instrument should be applied, and tissue of thepatient to which the energy applicator should not be applied. Thepatient positioning sub-system and/or the movable support may then beactuated (with the motors and points of movement and/or overlap,positioned outside of the sterile operating field, below the steriledrape, for example), not interfering with a patient's, surgeon's, and/orother surgical assistant's movement.

In a preferred form, the support includes an extension, preferablyangled, and the drive mechanism is coupled to the extension. Theextension includes means for adjusting the height of the support. Themeans include a plurality of generally spaced openings on the extensionand a pin for releasably locking the extension in a predeterminedposition through such spaced openings. In one exemplary embodiment, thesupport also includes an angled extension that either fits into orbecomes a sleeve, wherein the height of the support is verticallyadjustable by aligning different holes in the sleeve with acomplementary opening at the end of a thrust tube, for example, andsecuring the thrust tube and sleeve with a linchpin, for example.

It is envisioned, in one exemplary embodiment, that the autonomouspatient positioning sub-system is communicatively coupled with anavigation sub-system and therefore, directly or indirectly, to asurgical manipulator. The navigation sub-system is configured tocooperate with the patient positioning sub-system to position thesupport with respect to virtual boundaries that currently exist, and/orare calculated/expected to exist, as the surgery progresses.

The navigation sub-system is configured to track movement of variousobjects in the operating room. Such objects include, for example,surgical instrument(s), the femur of the patient, and the tibia of thepatient, the retractor(s), the knee joint stabilizer(s), the patientpositioning sub-system, or components and tissues related thereto. Thenavigation system also tracks these objects for purposes of operatingthe scheduled surgery routine, displaying their relative positions andorientations to the surgeon, for purposes of controlling or constrainingmovement of the surgical instrument, and/or the patient positioningsub-system, relative to virtual cutting boundaries, associated with thefemur and tibia.

Navigation Sub-System

It is envisioned, in one exemplary embodiment, that the navigationsub-system comprises a localizer, for example, an optical localizercomprising a sensing device, for example, an optical sensor. If anoptical localizer, the camera unit may be mounted on an adjustable armto position the optical sensors with the necessary field ofview/exposure, ideally, free from obstruction. Position and orientationsignals and/or data are transmitted to the navigation computer forpurposes of tracking objects. Other types of localizers are envisioned.

More specifically, in one exemplary embodiment, the navigationsub-system is a personal computer or laptop computer. Navigationcomputer has a display, central processing unit (CPU) and/or otherprocessors, memory, and storage. The navigation computer is loaded withsoftware. The software converts the signals received from the localizerinto data representative of the position and orientation of the objectsbeing tracked. One of ordinary skill in the art would understand how tocode the necessary software in view of this disclosure.

Further, the navigation sub-system includes a navigation processor and aboundary generator module operable on the navigation processor. Theboundary generator module is configured to generate the boundary basedon a plurality of inputs. In certain exemplary embodiments, the systemcomprises a support portion tracking device to track movement of thesupport and the necessary software, for example, a localization engineconfigured to receive data from the localizer. The system also comprisesa first boundary tracking device to track movement of a first of theplurality of virtual boundaries wherein the first virtual boundary isassociated with the anatomy to be treated. The system further comprisesa second boundary tracking device to track movements of a second of theplurality of virtual boundaries wherein the second virtual boundary isassociated with an object to be avoided by the instrument, etc.

Further, prior to the start of any surgical procedure, relevant data isloaded into the navigation processor. Based on the position andorientation of the tracking data, the navigation processor determinesthe position of the working end of the surgical instrument and theorientation of the surgical instrument relative to the tissue againstwhich the working end is to be applied. In some embodiments, thenavigation processor forwards the data or related data to a manipulatorcontroller. The manipulator controller can then use the data to controla robotic manipulator. Further, in some embodiments of the presentsolution, the navigation processor forwards the data or related data toa controller sub-system. The controller sub-system can then use the datato control a motorized patient positioning sub-system.

Controller Sub-System

It is envisioned, in one exemplary embodiment, that a controllersub-system, is configured to receive information from the navigationsystem and/or other components or sub-systems, to control a motorizedsupport portion of a patient positioning sub-system. The controller alsois configured to guide movement of the support portion of the patientpositioning sub-system, for example, relative to each of the first andsecond virtual boundaries as the first and second virtual boundariesmove relative to one another, or relative to other objects or tissue,during the surgery. In some exemplary embodiments, the controller isconfigured as a remote device (from the point of the view of the patientpositioning sub-system) for actuating the drive mechanism of the patientpositioning sub-system.

More specifically, in one exemplary embodiment, the controllersub-system is a personal computer or laptop computer. The controllersub-system has a display, central processing unit (CPU) and/or otherprocessors, memory, and storage. The controller sub-system is loadedwith software.

Further, the navigation system may leverage a plurality of dynamicvirtual boundaries to guide movement of the patient positioningsub-system via the controller sub-system. The navigation systemleverages the modeled virtual constraint boundaries, to actuate, via thecontroller sub-system, motors that drive movement of the support of thepatient positioning sub-system. The models may be displayed on thedisplay of the remote, controller sub-system to show how movement of thepatient positioning sub-system affects locations of the surgery objectsand the virtual boundaries. Further, the controller sub-system may beconfigured to communicate with the manipulator controller, for example,to guide the manipulator relative to these virtual constraintboundaries, and relative to the movement of the patient positioningsub-system.

In this way, the device of the present solution provides convenience forthe surgeon by permitting remote and automous “smart” operation of thedrive mechanism of the patient positioning sub-system. The presentsolution also provides a method for positioning a patient during asurgical procedure comprising positioning a patient on an operatingtable; positioning a movable support against a predetermined portion ofa patient's body outside of the sterile operating field; causing thesupport to move by automatically actuating a drive mechanism to providelinear movement of the support to cause the patient to move to anoptimal position for a surgical procedure in uninterrupted fashion.

Robotic Surgical Manipulator Device

It is envisioned, that the instrument or tool of the robotic surgicalmanipulator device may be configured as, but not limited to: burs; drillbits; saw blades; ultrasonic vibrating tips; electrode tips; RFelectrodes; cauterizing and ablation tips; and light emitting tips.

Software

It is envisioned, in one exemplary embodiment, that software modules arerun on the navigation processor, or the controller sub-system, or anyother component comprising a processor and memory. One of these modulesis a boundary generator that generates a map that defines one or moreboundaries between the tissue to which the instrument should be appliedand the tissue to which the instrument should not be applied. An inputinto the boundary generator may include preoperative images of the siteon which the procedure is to be performed, and/or the ComputerizedTomography (CT Scan) information, and/or the anthropometricsinformation. If the manipulator/instrument is used to selectively removetissue so the patient can be fitted with an implant, a second input intothe boundary generator is a map of the shape of the implant, dimensionsand size information, variance in manufacture, etc. Further, an inputinto the boundary generator is the surgeon's settings. These settingsinclude the practitioner's settings indicating to which tissue theinstrument should be applied. If the instrument is used to removetissue, the settings identify the boundaries between the tissue to beremoved and the tissue that remains after application of the instrument.If the manipulator is used to assist in the fitting of an orthopedicimplant, these settings define where over the tissue the implant shouldbe positioned. Other inputs are envisioned. Based on the input data andinstructions, boundary generator generates a map that defines theinstrument boundaries.

Another one of these exemplary modules is a tool path generator that mayreceive the same general input(s) as those applied to the boundarygenerator. Based on these inputs, the tool path generator generates atool path. The tool path generator receives as inputs, for example, theimage of the tissue, data defining the shape of the boundary, and thesurgeon's setting regarding the location of the boundary. For anorthopedic surgical procedure, the boundary is typically the shape ofthe implant; the surgeon setting is often the position of the implant.Once a procedure begins, the tool path generator may also receiveadditional data. Based on this data, the tool path generator may revisethe tool path. It should be appreciated that, based on this data, thetool path generator defines the tool or cutting path. It should also beappreciated that, based on this data, boundary constraints are generatedfor the tool or cutting path.

Another one of these exemplary modules is a localization engine thatreceives as inputs data, for example, sensor data and tracking data,regarding the surgical instruments, patient tissue, system componentsand sub-systems. Based on these signals, in one exemplary embodimentdealing with the patient positioning sub-system, the localization enginedetermines the position and pose of the bone(s), and the state of thepatient positioning sub-system, and the orientation and positioning ofthe components thereof. Further, the localization engine forwards thesignals representative of its work to a coordinate transformer, forexample.

Another one of these exemplary modules is a coordinate transformer thatreferences the data that defines the relationship between thepreoperative data of the patient, tool, and system, etc. and the currentstate thereof. The coordinate transformer may also store the dataindicating the relative nature of surgical object and tissue as comparedto other surgical objects and tissue.

Another one of these exemplary modules is a removed material logger thatcontains a map of the volume of the tissue to which the instrument is tobe applied. Often this is a map of a volume of tissue that is to beremoved. Other data that goes into maintaining this map may come fromthe data describing the shape of the implant and the personal setting ofthe surgeon, and the data related to how changing the patientpositioning device affects the position and pose of the bone(s). Othersources of data for defining this volume including mapping data obtainedat the start of the procedure. Further, the logger may also collect dataidentifying the on-patient locations to which the instrument is to beapplied, not to be applied, has already been applied, etc. This data maybe based on the manipulator tracking the movement of the arms, theplatform of the patient positioning system, etc. This data may be basedon the commanded or measured pose data. Alternatively, this data may begenerated based on the data describing the movement of the tool tracker.Further, the logger may transform the data regarding movement of theinstrument and the tool tracker into data that defines where, relativeto the bone, the instrument has moved, and possibly how the patientpositioning sub-system contributed to this. The logger stores the data.

Another one of these exemplary modules is actually a set of modules thatperform behavior control. Behavior control is the process of generatinginstructions that indicate the next commanded pose for the instrument. Asecond set of software modules perform motion control. One aspect ofmotion control is the control of the manipulator. The motion controlprocess receives data defining the next commanded pose of the instrumentfrom the behavior control process, for example. Based on this data, themotion control process determines the next position of the joint anglesof manipulator, for example. A second aspect of motion control is theproviding feedback to the behavior control modules based on theconstraints of the manipulator. The motion control modules also monitorthe state of the manipulator to detect if external forces/torques arebeing applied to or objects are in contact with the manipulator orinstrument or any component of the system.

Certain embodiments disclosed will become more apparent from thedrawings and following description.

FIG. 1 is an illustration of an exemplary embodiment of a new and usefulsystem that positions a patient, via an autonomous patient positioningsub-system, and which operates in conjunction with a robotic surgicalmanipulator device. The system 1 positions a patient as needed for thesurgery, via a patient positioning sub-system 10, wherein thepositioning of the patient is an autonomous mode, coordinated with theapplication of the surgical instrument 160. The positioning of thepatient is based at least in part on the demands and requirements andboundary-requirements, etc. of the manipulator 50, the surgicalnavigation system 210, the controller sub-system 36 of the patientpositioning sub-system 10.

An exemplary manipulator 50 used to apply a surgical instrument 160 to apatient 600 is shown. The manipulator 50 comprises an end effector 110to which the surgical instrument 160 is attached. The manipulator 50positions the end effector 110 to position and orient the surgicalinstrument 160 so that the instrument performs the intendedmedical/surgical procedure on the patient 600. The manipulator 50 isused in conjunction with a surgical navigation system 210 and acontroller sub-system 36, as well as various other components describedherein.

The manipulator 50 includes a cart 52. The cart 52 includes awheel-mounted frame. A shell 56 is disposed over the frame. Themanipulator 50 includes lower and upper arms 68 and 70, respectively.Each arm 68 and 70 includes a four bar linkage. In certain exemplaryembodiments, the manipulator 50 includes a number of interconnectedlinks. These links may be connected together in series and/or parallel.These links may form two parallel four bar linkages with the necessaryactuators and electrical motors, as is understood by a person havingordinary skill in the art. The instrument 160 is connected to the distalend of the links. Generally each pair of adjacent links is connected bya joint. The position of the links is set by actuators associated withthe joints.

The surgical navigation system 210 monitors the position of the endeffector 110 and the patient 600 and the patient positioning sub-system10. The navigation sub-system 210 comprises a localizer 216 comprisingoptical sensor(s), and other sensors to successfully track objects andtissue during the surgery. The localizer 216 receives signals from, ortransmits signals to, the trackers on objects and tissue for thesurgical procedure. If the localizer 216 receives light signals from thetrackers, the localizer is called a camera or optical localizer. Thesurgical navigation system 210 also includes a navigation processor 218.If the localizer 216 receives signals from the trackers, the localizer216 outputs to the processor 218 signals based on the position andorientation of the trackers relative to the localizer. If the trackersreceive signals from the localizer 216, the trackers output to theprocessor 218, based on the position and orientation of the trackers tothe localizer, or via some other indirect localizing method.

Based on the received signals, the navigation processor 218 generatesdata indicating the relative positions and orientations of the trackersto the localizer 216. In some versions, the surgical navigation system210 may include the trackers, sensor system, localizer, and/or computersystems.

Based on this monitoring, the surgical navigation system 210 determinesthe position of the surgical instrument 160 relative to the site on thepatient to which the instrument is applied, and the position of thepatient positioning sub-system 10. Further, a path of travel along whichthe instrument 160 should be applied to the patient tissue is generated.At least the basic version of this path may be generated prior to thestart of the procedure. The surgical navigation system 210 calculatesthe forces and torques necessary to move the instrument along apredefined path of travel. Based on these forces and torques, themanipulator 50 moves the surgical instrument 160, via the end effector110, along the predefined path of travel.

More specifically, prior to the start of the surgical procedure,additional data is loaded into the navigation processor 218. Based onthe position and orientation of the trackers, or the data received fromcomponent sensors and processors, and the previously loaded data, thenavigation processor 218 determines the position of the working end ofthe instrument 160 and the orientation of the end effector 110, and theposition of the platform, etc. The navigation processor 218 forwardsthis data to the manipulator controller 124. Further, the controllersub-system 36 (see FIG. 2 and the related Disclosure for a more detaileddescription) forwards this data to the motor 26 of the patientpositioning sub-system 10.

Next, the manipulator 50 responds to the forces and torque commanded bythe surgical navigation system 210 on the instrument 160 to position theinstrument 160. In response to these forces and torques, the manipulator50 mechanically moves the instrument 160 in a manner that emulates theintended path. As the instrument 160 moves, the surgical manipulator 50and surgical navigation system 210 cooperate to determine if theinstrument 160 is within the target boundary. This boundary is withinthe patient 600 and beyond which the instrument 160 should not beapplied. The manipulator 50 selectively limits the extent to which theinstrument 160 moves. Further, the manipulator 50 constrains the endeffector 110 from movement that would otherwise result in theapplication of the instrument 160 outside of the defined boundary, viaupdated monitoring and analysis of the real world surgical conditions.

Said another way, the virtual cutting boundaries are created todelineate sections available to the instrument 160 and sectionrestricted to the instrument 160. The surgical navigation system 210,via the localizer 216, tracks movement of the end effector110/instrument 160 with respect to the virtual cutting boundary todetermine a position and/or orientation of the end effector110/instrument 160 relative to the virtual cutting boundary. Further, asis discussed in greater detail herein, prior to the start of theprocedure additional data was loaded into the navigation processor 218.Based on the position and orientation of the trackers (which may havebeen applied by the surgeon to patient 600 to define the surgical site),and the previously loaded data, and the virtual cutting boundaries, andthe state of the patient positioning sub-system 10, etc., the navigationprocessor 218 forwards the data to the manipulator controller 124 andthe controller sub-system 36 (see FIG. 2 and the related Disclosure fora more detailed description). The navigation processor 218 alsogenerates image signals that indicate the relative position of theinstrument 160 to the surgical site.

These image signals are applied to an interface 220, also part of thesurgical navigation system 210 in this embodiment. The interface 220,based on these signals, generates images that allow a surgeon to viewthe relative position of the instrument 160 to the surgical site. Theinterface 220 includes a touch screen, or other input/output device thatallows entry of commands, and is situated outside of the sterile field.

Further, the patient positioning sub-system 10 is configured forpositioning the patient 600 on an operating table 12. The operatingtable 12 is segmented and includes a head and upper body support section14, a trunk support section 16, and a leg support section 18. Theoperating table 12 also includes a pair of stand-off rails 20substantially running the length of the operating table 12.

The patient positioning sub-system 10 includes a support 22 that isadapted to be positioned beneath the patient's foot, specifically, upagainst the heel and/or arch of the foot of the patient 600. The patientpositioning sub-system 10 also includes a drive mechanism 24 for movingthe support 22 along a generally linear path towards the feet/bottom ofthe operating table 12 or towards the top/head of the operating table12. The drive mechanism 24 is configured, at least in part, as anelectrically powered linear actuator. The actuator includes a motor 26with a worm gearing and a lead screw, and a thrust tube 28. Power to themotor 28 causes rotation of the worm-screw-drive resulting in the thrusttube 28 either extending or retracting.

The bracket 30 is used to secure the drive mechanism 24 to the supportrail 20. Thumbscrews, clamps, or other attachment devices are used. Thebracket 30 and attachments are designed so that the drive mechanism 24is readily moveable from one side of an operating table 12 to anopposite side or end, depending upon the particular surgical procedureto be performed. Further, the drive mechanism 24 is driven by theelectric motor 26. A source of power for the drive mechanism 24 isprovided through electrical plug 32.

The support 22 is padded for the comfort of patient 600. In theembodiment shown, the support 22 is in the form of a cylinder. Thesupport 22 includes an angled extension 38 that either fits into orbecomes a sleeve 40. The sleeve 40 includes a plurality of spacedopenings 42 that extend through the sleeve 40. In the embodiment shown,the height of the support 22 is vertically adjustable by aligningdifferent holes 42 in the sleeve 40 with a complementary opening at theend of the thrust tube 28 and securing the thrust tube and sleeve with alinchpin 44.

In use, the patient 600 is positioned on operating table 12 and thepatient positioning sub-system 10 is installed so that movable support22 is properly positioned against the patient's foot, without need forstraps or engagement, and the patient 600 is resting free on the movablesupport 22. As shown, the patient positioning sub-system 10 of thepresent solution is positioned and used outside of the sterile operatingfield and does not interfere with the surgeon's and/or surgicalassistant's movements. This is in stark contrast to the prior art.

In particular, the movement of support 22 causes flexing of the knee ofpatient 600 to an optimal position for a surgical procedure, and foradjusting of the virtual boundaries, as needed. The patient positioningsub-system 10 is actuated at the movable support 22, with the motor 26and the thrust tube 28, and other electronics and points ofmechanical-overlap, such as the bracket 30, the electrical plug 32, theangled extension 38, the sleeve 40, the spaced openings 42, and thelinchpin 44, and the controller sub-system 36, positioned outside of thesterile operating field, below the sterile drape 58.

In this light, a method of controlling the support 22 of the patientpositioning sub-system 10 is provided. The surgical navigation system210, despite being illustrated and enabled as its own independentcomponent in the system 1, cooperates with the patient positioningsub-system 10 components to position the support 22 based at least inpart on the virtual boundaries. The navigation processor 218 determinesthe relative location of the instrument 160 to a boundary, and via thecontroller sub-system 36 determines the relative location/positioning ofthe support 22 of the patient positioning sub-system 10 with the patient600 in place (see FIG. 2 and the related Disclosure for a more detaileddescription).

In the event it appears that the navigation processor 218 demands,requires, or needs positioning of the instrument 160 beyond theboundary, the manipulator 50 does not allow this movement of theinstrument 160. Instead, should the navigation processor 218 determinethat the needed path/point for the instrument 160 would result in theinstrument 160 triggering or exceeding a boundary, which the instrument160 should not cross, the navigation processor 218 directly orindirectly (1) prevents the instrument 160 from movement beyond theboundary, and (2) adjusts the support 22 of the patient positioningsub-system 10 and/or any other component or sub-system of the patientpositioning sub-system 10, such as the motor 26 and the thrust tube 28,to reposition the tissue to be treated, and (3) reassesses/determinesthe relative location of the instrument 160 to the new boundarycondition, after adjustment of the patient positioning sub-system 10 at(2). The robotic surgical manipulator device 50 may then continue toattempt to move the instrument as demanded, required, or needed prior to(1).

FIG. 2 is a functional block diagram of a number of modules thatcollectively cooperate to control actuation of the overall system 1 ofFIG. 1. Mounted to cart 52 is a manipulator controller 124 and a jointmotor controller(s) 126. The manipulator controller 124 is a high speedgeneral purpose digital computer in this embodiment. The manipulatorcontroller 124 determines the location to which the surgical instrument160 should be moved based on data from force/torque sensors, encoders,the surgical navigation processor 218, as well as other information forthe other portions of the system 1 as is described herein. Based on thisdetermination, the manipulator controller 124 determines the extent towhich each arm-forming link needs to be moved in order to reposition thesurgical instrument 160 and/or guide the surgical instrument 160 along adesired path. The data regarding where the links are to be positionedare forwarded to the joint motor controllers 126.

Each joint motor controller 126 regulates the application ofenergization signals to a single one of the joint motors. The primaryfunction of the joint motor controller 126 is to apply energizationsignals to the associated motor so that the motor drives the associatedjoint to an angle that approaches the commanded joint angle.

A touch screen display 128 or other user input/output unit is alsomounted to cart 52. The display 128 is attached to a user interface 130also attached to the cart. The user interface 130 controls thepresentation of information on the display 128 and initially processesuser-generated commands/inputs entered over the display 128.

The tool controller 132 supplies energization signals to the surgicalinstrument 160. The tool controller 132 typically includes: a powersupply; power control circuit; a user interface; an application specificdata processing unit (components not illustrated). The power supplyconverts the line voltage into power signals that can be applied to thesurgical instrument 160. The power controller circuit selectivelyapplies the power signals to the power generating unit integral with theinstrument 160.

In some embodiments, the manipulator display 128 functions as the userinterface and output display for the tool controller 132. The userinterface 130 allows the practitioner to enter instructions regardinghow she/he wants the instrument 160 to function as a back stop to theautomation provided by the system 1. Commands to set and adjust theoperational settings of the tool controller 132 and instrument 160 areforwarded from the user interface 130 to the tool controller 132.

The tool controller 132 receives the instructions entered over the userinterface 130 and other data necessary to operate the instrument 160 asis described in detail herein. Based on this data, the tool controller132 outputs energization signals that cause the instrument 160 tooperate in the manner instructed by the navigation processor 218, andthe manipulator controller 124, and the other components that contributeto automation of the system 1.

For example, the controller sub-system 36, is configured to receiveinformation from the navigation processor 218 and/or other modules, andtransmit communication signals to the tool controller 132, as needed, tocontrol the motorized support portion 22 of the patient positioningsub-system 10, based at least in part on at least a first and secondvirtual boundaries ascertained by the navigation processor 218, as wellas other information from the other portions of the system 1 as isdescribed herein. The controller sub-system 36 also is configured toguide movement of the support 22, for example, relative to each of thefirst and second virtual boundaries as the first and second virtualboundaries are moved/commanded to be moved, relative to one another, orrelative to other objects or tissue, during the surgery.

Like the tool controller 132, the controller sub-system 36 suppliesenergization signals to the motor 26. The controller sub-system 36typically includes: a power supply; power control circuit; a userinterface; a data processing unit. The power supply converts the linevoltage into power signals that can be selectively applied to rotate theworm gearing and a lead screw in the motor 26, resulting in the thrusttube 28 either extending or retracting. The user interface 130 alsoallows the practitioner to enter instructions regarding how she/he wantsthe motor 26 to function, as a back stop to the automation provided bythe system 1.

In some exemplary embodiments, the manipulator display 128 functions asthe user interface and output display for the controller sub-system 36.Commands to set and adjust the operational settings of the controllersub-system 36 and motor 26, etc., are forwarded from the user interface130 to the controller sub-system 36.

FIG. 3 is a magnified, side view of the exemplary system of FIG. 1. Asis described in greater detail herein, in some surgical procedures, itis necessary to move the limb of the patient 600 to a first position forinitial work, and then to move that limb or body portion to second,third or more optimal positions as the surgery proceeds. In this way,the surgical boundaries may be modified or adjusted throughout thesurgery. Although the system 1 automates the movement of the patientpositioning sub-system 10, in conjunction with the automation of themanipulator 50 (partially shown), under some circumstances, the surgeonmay need to remotely command the system 1.

For purposes of the patient positioning sub-system 10, the surgeon mayuse a foot-operated switch 34 to remotely actuate the drive mechanism ofthe motor 26. Again, as is described herein, all of this is outside thesterile surgical field beneath the drape 58. Depending on the motiondesired, the surgeon may cause the thrust tube 28 to move as shown inFIG. 3 by pressing on the corresponding end of the switch 34. Activationof switch 34 causes the controller sub-system 36 to drive motor 26 in adesired direction.

Further, the controller sub-system 36 receives the instructions enteredover the user interface 130, or foot-operated switch 34, and other datanecessary to operate the motor 26, as is described in greater detailherein. Based on this data, the controller sub-system 36 outputsenergization signals that cause the motor 26 to operate in the mannerinstructed by the controller sub-system 36, the navigation processor218, and the manipulator controller 124, and the other components thatcontribute to automation of the system 1, as is described in greaterdetail herein.

In this way, the navigation processor 218 may leverage a plurality ofdynamic virtual boundaries (not shown) and automated robotic surgeryalgorithms, and guide movement of the support 22 through commands fromthe controller sub-system 36. The navigation processor 218 leverages themodeled virtual constraint boundaries, to actuate, via the controllersub-system 36, movement of the support 22 of the patient positioningsub-system 10. The models used for automation may be displayed on adisplay 128 (not shown) to show how movement of the patient positioningsub-system 10 affects locations of the tracked objects (tracked objectspreviously placed along and around the surgical site by the surgeon).Further, the controller sub-system 36 communicates with the manipulatorcontroller 124 (not shown) to help guide the links of the manipulator50, and the corresponding movement of the surgical instrument 160,relative to these virtual constraint boundaries, and the movement of thepatient positioning sub-system 10, etc.

Emphasis should be placed on the sterile drape 58 on the operating table12. The drape 58 functions as a sterile barrier. Unlike prior art limbholders for arthroplasty, which are designed to be attached on top ofthe sterile drape 58, and which makes it difficult, if not impossible,to provide an optimal sterile barrier/easy-cleanup system, the patientpositioning sub-system 10 is positioned directly on the operating table12. The patient positioning sub-system 10 is installed such that themovable support 22 is properly positioned.

In this way, the entirety of the patient positioning sub-system 10 andthe movable support 22, as well as the other structural and mechanicalfeatures of the system 1, other than the manipulator 50, are positioned,used, and/or actuated outside of the sterile operating field (e.g, belowthe sterile drape 58 with the patient's 600 leg exposed outside thesterile drape 58, the leg resting on top of the sterile drape 58, whichis itself resting on top of the support 22). As the support 22 iscylindrical and configured to roll or skid on top of the operating table12, as it is moved by the motor 26, the support 22 will not rip thesterile drape 58 even if the surgeon or the surgery personnel need topull the sterile drape 58 in order to adjust the slack, etc. Thismaintains the integrity of the sterile operating field and positions anycomplex mechanical points of overlap, or pivot, or actuation, away frompossible contamination, which would require difficult, costly, andcomplex sterilization and clean-up protocols.

Further, emphasis should be placed on the composition and positioning ofthe drive mechanism 24 of the system 1. The drive mechanism 24 issimilarly and/or tangentially composed to the actuation mechanisms ofthe manipulator 50. This is of importance because the patientpositioning sub-system 10 is easily implemented and incorporated intothe autonomous surgical system, and into the software and hardwarerequirements, without necessitating extreme and/or complex changes.

As such, the system 1 provides convenience for the surgeon by permittingremote and automous “smart” operation of the drive mechanism of thepatient positioning sub-system 10. The system 1 also provides a methodfor positioning a patient 600.

Referring now to FIG. 4, the FIGS. are a flow chart of an exemplaryembodiment of a method of using the system of FIGS. 1-3. One of ordinaryskill in the art understands that the exemplary method 1000 may beperformed by various means that do not limit the scope of the presentdisclosure. The flowchart of the method 1000 is presented from theperspective of controlling the surgical manipulator 50 based on implantparameters, and on the position of the patient positioning sub-system10. The manipulator 50, the navigation system 210, and the patientpositioning sub-system 10 are envisioned to be employed in a surgicalprocedure to repair a joint of the patient 600, such as a knee joint,hip joint, shoulder joint, and the like.

More specifically, at block 1010 of FIG. 4A, prior to the procedure, apre-operative image, such as an MRI or CT scan is used to create a threedimensional model of the patient's joint. For instance, an MRI or CTscan is used to create a 3D model of the tibia and femur of the patient600. At block 1012 of FIG. 4A, tracking devices with active or passivemarkers, are mounted to each of the tibia and femur of patient 600 usingconventional methods, for purposes of tracking the tibia and femurduring the procedure and for registering the pre-operative images to theanatomy.

At block 1014 of FIG. 4A, the navigation system 210 receives informationon the shapes of the implants to be implanted on the femur and tibia ofpatient 600, the boundaries of the material intended to be removed fromthe patient's joint, and data defining how relative changes to thepatient positioning sub-system 10 affect the position and pose of thefemur and tibia of patient 600, etc. Measurements of the implants andthe instrument 160 may be made by a coordinate measuring machine (CMM),laser measuring device, video measuring device, micrometer, profileprojector, or other suitable devices.

At block 1016 of FIG. 4A, the navigation system 210 creates virtualboundaries on the femur and tibia of patient 600 based on the shapes ofthe implants and the current position of the joint, etc., as it isloosely resting on the platform portion 22 of the patient positioningsub-system 10, over the surgical drape 58. The three-dimensional shapesof the boundaries correlate to target volumes of material to be removedfrom the femur and/or tibia for the implants while the patient 600 is inthat particular position and pose. The navigation system 210 includesthe navigation processor 218 running boundary generator softwareoperable to generate the boundary based on the plurality of inputs asdescribed herein.

Notably, by tracking the positions and/or orientations of the instrument160, the tibia, and the femur of the patient 600, and the current stateof the patient positioning sub-system 10, during the procedure, thedistal end or tip of the instrument 160 is maintained within thesurgical boundaries. As the boundaries are tied to the anatomy of thepatient 600, tracking movement of the anatomy also tracks movement ofthe boundaries since the anatomy of the patient 600 being treated maymove during the surgical procedure.

The method advances to block 1018 of FIG. 4B and includes the steps ofbeginning removal of the target volume of the femur and tibia of patient600 with the instrument 160 attached to the surgical manipulator 50. Atblock 1020 of FIG. 4B, the navigation processor 218 determines therelative location of the instrument 160 to the boundary(ies), and viathe controller sub-system 36, for example, determines the relativelocation/position of the support 22 of the patient positioningsub-system 10 with the patient 600 in place.

Notably, to perform this process, the controller 124 and the processor218 and the controller sub-system 36, etc. collectively keep track of anumber of different system 1 components and the patient 600.

At block 1022 of FIG. 4B, in the event it appears that the navigationprocessor 218 demands, requires, or needs positioning of the instrument160 beyond the boundary, the navigation processor 218 does not allowthis movement of the instrument 160. Instead, should the navigationprocessor 218 determine that the needed path/point for the instrument160 would result in the instrument 160 triggering a boundary, which theinstrument 160 should not cross, the navigation processor 218 directlyor indirectly, at block 1024 of FIG. 4B, prevents the instrument 160from moving beyond the boundary, and, at block 1026 of FIG. 4C, adjuststhe support 22 of the patient positioning sub-system 10 via actuation ofthe motor 26 via the controller sub-system 36, for example, toreposition the joint being treated, and, at block 1028 of FIG. 4C,reassesses/determines the relative location of the instrument 160 to thenew boundary condition after adjustment of the patient positioningsub-system 10 at block 1026. In this way, embodiments of the solutionmay very accurately, and precisely, position the patient's joint suchthat the boundaries of the surgical site are optimally defined forapplication of the surgical instrument 160.

As part of this re-positioning, the manipulator controller 124 does notmove the instrument 160 outside of defined boundaries, but thecontroller sub-system 36 does position the platform 22 to adjust thedefined boundaries, as needed and demanded by surgery. At block 1030 ofFIG. 4C, in the event it again appears that the navigation processor 218demands, requires, or needs positioning of the instrument 160 beyond theboundary, the navigation processor 218 does not allow this movement ofthe instrument 160. Instead, should the navigation processor 218determine that the needed path/point for the instrument 160 would resultin the instrument 160 triggering a boundary, which the instrument 160should not cross, the method reverts back to block 1026. In the eventthat it does not appear that the navigation processor 218 demands,requires, or needs positioning of the instrument 160 beyond theboundary, the navigation processor 218 does allow the movement.

At block 1032 of FIG. 4C, the method advances and includes the steps ofcontinuing removal of the target volume of the femur and tibia ofpatient 600 with the instrument 160. The method then advances to block1034 of FIG. 4C and includes the steps of placing the actual implantinto the joint. The method then ends.

In this way, the surgical navigation system 210 cooperates with thepatient positioning sub-system 10 components to position the support 22based at least in part on the virtual boundaries, based on the exemplarymethod of use as described herein. In other more detailed exemplaryembodiments, the method may include the controller sub-system 36receiving information from the navigation processor 218 and/or othermodules, and transmitting communication signals to the tool controller132, as needed, to control the motorized support portion 22 of thepatient positioning sub-system 10, based at least in part on at least afirst and second virtual boundaries, as well as other information fromthe other portions of the system 1, as is described herein. Thecontroller sub-system 36 also may guide movement of the support 22, forexample, relative to each of the first and second virtual boundaries asthe first and second virtual boundaries are moved/commanded to be moved,relative to one another, or relative to other objects or tissue, duringthe surgery.

Certain steps in the exemplary method described herein naturally precedeothers for the solution to function as described. However, the solutionis not limited to the order of the steps described if such order orsequence does not alter the functionality of the system and method ofthe present disclosure. That is, it is recognized that some steps mayperformed before, after, or parallel (substantially simultaneously with)other steps without departing from the scope and spirit of the solution.In some instances, certain steps may be omitted or not performed withoutdeparting from the solution. Further, words such as “thereafter”,“then”, “next”, etc. are not intended to limit the order of the steps.These words are simply used to guide the reader through the descriptionof the exemplary method.

FIG. 5 is an illustration of a second exemplary embodiment of a new anduseful system that positions a patient, via an autonomous patientpositioning sub-system, and which operates in conjunction with a roboticsurgical manipulator device, which also includes an autonomous side pad302. The system 2 is identical to the system 1 except for the followingdescribed differences.

The system 2 positions a patient as needed for the surgery, via apatient positioning sub-system 10 and a side pad sub-system 300, whereinthe positioning of the patient is an autonomous mode, coordinated withthe application of the surgical instrument 160. Again, the positioningof the patient is based at least in part on the demands and requirementsand boundary-requirements, etc. of the manipulator 50, the surgicalnavigation system 210, and the controller sub-system 36 of the patientpositioning sub-system 10.

The surgical navigation system 210 monitors the position of the endeffector 110 and the patient 600 and the patient positioning sub-system10 and the side pad sub-system 300. Based on this monitoring, thesurgical navigation system 210 determines the position of the surgicalinstrument 160 relative to the site on the patient to which theinstrument is applied, and the position of the patient positioningsub-system 10 and the position of the side pad sub-system 300. Further,a path of travel along which the instrument 160 should be applied to thepatient tissue is generated.

More specifically, prior to the start of the surgical procedure,additional data is loaded into the navigation processor 218. Based onthe position and orientation of the trackers, or the data received fromcomponent sensors and processors, and the previously loaded data, thenavigation processor 218 determines the position of the working end ofthe instrument 160 and the orientation of the end effector 110, and theposition of the platform 22, and the position of the side pad 302. Thenavigation processor 218 forwards this data to the manipulatorcontroller 124. Further, the controller sub-system 36 forwards this datato the drive mechanism 24 of the patient positioning sub-system 10, andto the drive mechanism 304 of the side pad sub-system 300.

Next, the manipulator 50 responds to the forces and torque commanded bythe surgical navigation system 210 on the instrument 160 to position theinstrument 160. In response to these forces and torques, the manipulator50 mechanically moves the instrument 160 in a manner that emulates theintended path. As the instrument 160 moves, the surgical manipulator 50and surgical navigation system 210 cooperate to determine if theinstrument 160 is within the target boundary. The manipulator 50constrains the end effector 110 from movement that would otherwiseresult in the application of the instrument 160 outside of the definedboundary, via updated monitoring and analysis of the real world surgicalconditions.

The navigation processor 218 forwards the data to the manipulatorcontroller 124 and the controller sub-system 36, for controlling thepatient positioning sub-system 10 and the side pad sub-system 300. Thepatient positioning sub-system 10 and the side pad sub-system 300 areconfigured for positioning the patient 600 on an operating table 12.

Similar to the patient positioning sub-system 10, the side padsub-system 300 includes a side support/side pad 302 that is adapted tobe positioned against the side of the patient 600, specifically, againstthe thigh of the patient 600 on the side to be operated on. The side padsub-system 300 also includes a side pad drive mechanism 304 forlaterally moving the side support 302 relative to the table 12 to adjustthe lateral position of the patient's 600 leg. The drive mechanism 304is configured, at least in part, as an electrically powered linearactuator with a shorter stroke length than the drive mechanism 24. Assuch, via a bracket like bracket 30, the drive mechanism 304 may besecured beneath the operating table 12 so as to leverage the shorterstroke length, while still positioning the drive mechanism 304 below thesterile surgical field/ drape 58. Further, the side support 302 ispadded for the comfort of patient 600. In the embodiment shown, the sidesupport 302 is in the form of a planar padding.

In use, the patient 600 is positioned on operating table 12 and thepatient positioning sub-system 10 and the side support 302 are installedso that movable support 22 is properly positioned against the patient'sfoot, and so that the movable side support 302 is properly positionedagainst the patient's outer thigh, without need for straps orengagement, and the patient 600 is resting free on the movable support22, and naturally falling outwards toward the side pad 302 (due topatient's 600 unconscious state).

In particular, the movement of support 22 causes flexing of the knee ofpatient 600 to an optimal position for a surgical procedure, and foradjusting of the virtual boundaries, as needed. Similarly, the movementof side support 302 causes a lateral movement inward or outward of theknee of patient 600 to an optimal position for the surgical procedure,and for adjusting of the virtual boundaries, as needed. The patientpositioning sub-system 10 is actuated at the drive mechanism 24 and theside support 302 is actuated at the drive mechanism 304.

In this light, a method of controlling the support 22 of the patientpositioning sub-system 10 is provided, and a method of controlling theside support 302 of the side support sub-system 300. The surgicalnavigation system 210 cooperates with the patient positioning sub-system10 components and the side support 302 components to position thesupport 22 and the side support 302 based at least in part on thevirtual boundaries. The navigation processor 218 determines the relativelocation of the instrument 160 to a boundary, and via the controllersub-system 36 determines the relative location/positioning of thesupport 22 and the side support 302 with the patient 600 in place.

In the event it appears that the navigation processor 218 demands,requires, or needs positioning of the instrument 160 beyond theboundary, the manipulator 50 does not allow this movement of theinstrument 160. Instead, should the navigation processor 218 determinethat the needed path/point for the instrument 160 would result in theinstrument 160 triggering a boundary, which the instrument 160 shouldnot cross, the navigation processor 218 directly or indirectly (1)prevents the instrument 160 from movement beyond the boundary, and (2)adjusts the support 22 and/or the side support 302, and/or any othercomponent or sub-system to reposition the tissue to be treated, and (3)re-assesses/determines the relative location of the instrument 160 tothe new boundary condition, after adjustment of the patient positioningsub-system 10 and/or the side support sub-system 300 at (2). The roboticsurgical manipulator device may then continue to attempt to move theinstrument as demanded, required, or needed prior to (1).

Systems, devices and methods for a patient positioning system used toposition body parts, such as a knee, during a medical or surgicalprocedure have been described using detailed descriptions of embodimentsthereof that are provided by way of example and are not intended tolimit the scope of the disclosure. The described embodiments comprisedifferent features, not all of which are required in all embodiments ofa magnetic prosthetic according to the solution. Some embodiments of thesolution utilize only some of the features or possible combinations ofthe features. Variations of embodiments of the solution that aredescribed and embodiments of the solution comprising differentcombinations of features noted in the described embodiments will occurto persons of the art.

It will be appreciated by persons skilled in the art that systems,devices and methods for a patient positioning system used to positionbody parts, such as a knee, during a medical or surgical procedure,according to the solution, are not limited by what has been particularlyshown and described herein above. Rather, the scope of systems, devicesand methods of a patient positioning system used to position body parts,such as a knee, during a medical or surgical procedure, according to thesolution, is defined by the claims that follow.

-   System 1-   System 2-   Patient Positioning Sub-system 10-   Operating table 12-   Head and Upper Body Support Section 14-   Trunk Support Section 16-   Leg Support Section 18-   Rails 20-   Support 22-   Drive Mechanism 24-   Motor 26-   The Thrust Tube 28-   The Bracket 30-   Electrical Plug 32-   Foot-Operated Switch 34-   Controller Sub-System 36-   Angled Extension 38-   Sleeve 40-   Spaced Openings 42-   Linchpin 44-   Manipulator 50-   Cart 52-   Shell 56-   Drape 58-   Lower Arms 68-   Upper Arms 70-   End Effector 110-   Manipulator Controller 124-   Joint Motor Controllers 126-   Display 128-   User Interface 130-   Tool Controller 132-   Surgical Instrument 160-   Surgical Navigation System 210-   Localizer 216-   Navigation Processor 218-   Interface 220-   Side Pad Sub-System 300-   Side Pad 302-   Side Pad Drive Mechanism 304-   Patient 600-   Method 1000

What is claimed is:
 1. An apparatus for positioning a patient during asurgical procedure comprising: a support adapted to be positionedagainst a patient's body, the support comprising means for adjusting theheight of the support, the support also comprising a drive mechanismwith actuator for moving the support along a generally linear path, andat least one bracket for mounting the drive mechanism to the side of anoperating table; and a remote device for actuating the drive mechanism,the remote device configured at least in part as a controller for thesupport, the controller communicatively coupled to a surgical navigationsystem, the surgical navigation system configured to cooperate with thecontroller to position the support with respect to a change demanded toa boundary, the boundary defining tissue of the patient to which anautomated surgical instrument should be applied and tissue of thepatient to which the surgical instrument should not be applied.
 2. Theapparatus for positioning a patient of claim 1, wherein the means foradjusting the height of the support comprises a vertical extension thatis angled.
 3. The apparatus for positioning a patient of claim 2,wherein the drive mechanism is coupled to the extension.
 4. Theapparatus for positioning a patient of claim 3, wherein the extensiondefines a plurality of generally spaced openings.
 5. The apparatus forpositioning a patient of claim 4, further comprising a pin forreleasably locking the extension in a predetermined position via thegenerally spaced openings.
 6. The apparatus for positioning a patient ofclaim 1, further comprising a foot-operated switch for the remotedevice, as an emergency override to the surgical navigation system, thefoot-operated switch configured to be communicatively coupled to theremote device.
 7. The apparatus for positioning a patient of claim 1,wherein the surgical navigation system comprises a surgical tracker, anavigation processor, and a boundary generator module running on thenavigation processor, and wherein the controller comprises a processorand a platform control module running on the remote device processor. 8.The apparatus for positioning a patient of claim 1, wherein the supportcomprises a cylindrical, padded component.
 9. The apparatus forpositioning a patient of claim 1, wherein the drive mechanism iselectrically powered.
 10. An apparatus for positioning a patient duringa surgical procedure comprising: a support adapted to be positionedagainst a portion of the patient's body, the support comprising meansfor adjusting the height of the support, the support also comprising afirst drive mechanism with actuator for moving the support along agenerally linear path, and at least one bracket for mounting the drivemechanism to the side of an operating table; a remote device foractuating the drive mechanism, the remote device configured at least inpart as a controller for the support, the controller communicativelycoupled to a surgical navigation system; and a side pad adapted to bepositioned against the patient's body, on the same side as the portionof the patient's body, the side pad comprising a second drive mechanismwith actuator for laterally moving the side pad relative to a side ofthe operating table, and at least one bracket for mounting the seconddrive mechanism to the side of an operating table, the remote devicealso configured for actuating the second drive mechanism of the sidepad, the surgical navigation system configured to cooperate with thecontroller to position the support and the side pad with respect to achange demanded to a boundary, the boundary defining tissue of thepatient to which an automated surgical instrument should be applied andtissue of the patient to which the surgical instrument should not beapplied.
 11. The apparatus for positioning a patient of claim 10,wherein the means for adjusting the height of the support comprises avertical extension that is angled.
 12. The apparatus for positioning apatient of claim 11, wherein the drive mechanism for the support iscoupled to the extension.
 13. The apparatus for positioning a patient ofclaim 12, wherein the extension defines a plurality of generally spacedopenings.
 14. The apparatus for positioning a patient of claim 13,further comprising a pin for releasably locking the extension in apredetermined position via the generally spaced openings.
 15. Theapparatus for positioning a patient of claim 10, further comprising afoot-operated switch for the remote device, as an emergency override tothe surgical navigation system, the foot-operated switch configured tobe communicatively coupled to the remote device.
 16. The apparatus forpositioning a patient of claim 10, wherein the surgical navigationsystem comprises a surgical tracker, a navigation processor, and aboundary generator module running on the navigation processor, andwherein the controller comprises a processor and a platform controlmodule and a side pad control module running on the remote deviceprocessor.
 17. The apparatus for positioning a patient of claim 10,wherein at least one of the first drive mechanism and the second drivemechanism is electrically powered.